[en] The process by which deuterons adsorbed into a palladium cathode combine to generate heat energy is enhanced under the control of an electrical current flowing around an all-metal circuit including the cathode. This current is an A.C. current very much greater than the ionic anode-cathode current involved in deuteron adsorption. It causes adsorbed deuterons to excite fusion-triggering vacuum energy fluctuations when traversing field boundaries inside the cathode in the presence of a strong electron counterflow. Deuterium may be absorbed into the cathode by electrolysis or by corona discharge. (author)